At the moment though the non-game software offered on Steam is fairly limited and Windows only with titles like 3DMark Vantage, GameMaker: Studio, and 3D-Coat. However, moving forward you can expect many more productivity applications to surface on the popular system. Mac OS X and Linux software will follow.
Those wishing to see the software offered via Steam can do so from SteamPowered.com. Meanwhile, the Steam Linux beta is getting underway.